Rotary grinding and polishing device



Sept. 12, 1933.

E. F. COOK ROTARY GRINDING AND POLISHING DEVICE Filed May 31, 1929 INVENTOR. 271760012 ATTO EYS,

Patented Sept. 12 1933' 1, ROTARY GRINDING "ANDPOLISYHING DEVICE v Eugene F. Cook,

Kansas City, Mo.

Application May 3 1, 1929. Serial No. 367,268 8 Claims. (01. 51-1841) This inventionrelates to rotary grinding and polishing devices, and moreespecially to devices of the class named, foroperation on the interior Walls of cylinders, particularly cylinders of internal combustion motors, and myobject is to produce a device-in which the grinding elements are rigidly positioned relative to the object operated on, 'as distinguished from the devices in which suchelementsapply a yielding pressure, with the consequent possibility of inaccurate grinding. Another object is to produce a grinder which will operate effectively Without lubrication of the cutting surfaces, and hence expedite the grinding operation.

A further object .is to provide means for effecting quick adjustment of the device from its minimumset to the maximum set. permitted by the cylinder to be operated on, "and other means for effecting additional expansion of the device as required duringthe' progress of the grinding or polishing operation.

Another object is to provide a construction whereby the honing or abrading elements of the device, because held rigidly, performtheir function without vibration and hence avoid the chattering which is common in and, impairs the-efficiency of operation and accuracy in the grinding operation. a W 4 Another object is to provide a construction which guards against the possibilityof a grind- .ing or polishing elementbeing dislodged through centrifugal action or force, in the event the device iswhollywithdrawn while at high speed, from a cylinder. M

With, these objects in view and -others, as hereinafter appear, the invention 'consists in certain novel and usefulfeatures of construction and combinations of parts as hereinafterdescribed and claimedgz and in order that it may be fully understoodjreferenceis to be had to the accompanying drawing, in which Figure 1 is an'endviewof the appliance with the grinding -arid polishing elementsomitted and thedrive" shaft section ,on the line I- I of Figure 2, the driveshaft beingindicated inihorizontal view in dotted lines.

Figure 2 isa side elevation of the complete device.

Figure 3 :is-a horizontal section on the line IIIIII of Figure 2. I

Figure 4 is a full size fragmentary central section of the device.

Figure 5 is a horizontal section .on the line 'V-V of Figure 4.'- r

r the pins 3 'of'the body portion, and the threaded Figure6 is a-face' view of a nut forming an element of the device. Figure 7 is a view of the outer or upper end 'of the body portion of the device. L

Figure 8.is a fragmentary vertical section of the inner or lower end of the body portion and pinion shaft. 1

Referring to the drawing in detail, 1 indicates a generally cylindrical body portion having a lonj gitudinal axial bore 2, and a series of project- 65 'ing pins 3 .at the outer or upper end,'the pins being arranged circularly and concentrically with respect to the bore 2. l

The body portion is provided with cross passages 4 intersecting or opening into the bore' 2. There are preferably four of these passages, arranged in pairs spaced apart, and extending in parallel relation, and the passages of each pair are disposed at opposite sides of the axial center of the" body portion. There-is a similarset of passages 4 which bear the relation to each other and to the bore 2 above explained, but which extend angularly, with respectto the first-named passages, preferably at right angles to the latter. Rack bars 5, extend through the first-named passages 4, and similar rack bars 6 extend through the other passages 4. The teeth 7 of the rack bars 5 and '6, are faced toward the axis of bore '2, and the opposite ends of the bars-of each pair, terminate in teethor lugs 8 of greater widththan the rack teeth, for a purpose which hereinafter appears. Each pair of parallel rack bars lying in the same longitudinal plane, is rigidly connected by a dovetail holder 9, and secured rigidly in each holder is a grinding stone or element 10', there being the'reforea pair of parallel grinding elements at opposite sides of the body portion and at opposite sides of the axial centerof the body portion, A pair of guides 1l,'preferably of non-abrasive .material; are, dovetailed in similar holders, car ried by the other pairs of rack bars in corresponding longitudinal planes, which guides are adapted to bear against the wallof a cylinder being trued by the grinding operation, so as to cooperate in centralizing the grinding elements in the cylindenand' also serving as guards against such vijbrationof the grinding elements against the cylinderas would result in a chattering noise and hence imperfect abrasive action on the cylinder.

A' cylindrical nut 12 normally fits against the upper or outer end of the body portion, and is formed witha chamber 13, and a circular series of holes 14, a number of which normally engage bore 15 of the nut is preferably of very coarse pitch, as indicated by Figure 6. Fitting rotatably in the bore 2, is an elongated gear pinion or pinion shaft 15a intermeshed with the rack bars so that when said pinion shaft, as it will be hereinafter termed, is turned in one direction or the other, it will impart outward or inward movement to all of the rack bars, it being noted that when the outward limit of movement of said rack bars is reached, the enlarged teeth or lugs of the rack bars will not mesh with'the' pinion shaft and hence will arrest the outward movement mentioned. The pinion shaft is of: substantially the same length asthe body portion 1 including the threaded portion of the nut 12, and the upper portion of said pinion shaft,

from a point substantially above the adjacent set of rack bars 5, is spirally threadedas at 16 at a pitch corresponding to that of the threaded bore 15 of the nut and engages the same so that longitudinal movement of, the pinion shaft through the nut shall effect-turning movement of theformer. The upper end of the pinion shaft has a threaded her-e17, for a purpose which hereinafter appears.

.Secured'rigidly in the chamber of the nut is a thrust plate 18, provided centrally with a perforated dome portion 19, and fitting upon the nut and thrust plate around the dome 19, isa spring washer 20. dome portion of the thrust plate and the wash-' er, is-a dome shaped wheel or rotatable cap 21 roughened peripherally as at 22 to provide a substantial hand grip for manual rotation of the wheel. or-cap. Secured rigidly in and depending centrally from the wheel or cap is a bolt 23; said bolt extending downthrough the dome 19 and engaging the threaded bore 17 of the pinion shaft. The preferred means for fastening the bolt rigidly to the wheel cap is by a cross pin 24, andsecured upon the bolt and engaging the under side ,of the-dome 19 is a thrust collar 25.-

As thus far described it will be apparent that by grasping the wheel or cap, or the nut 12 or both, and applying an upward pull, the bolt 23, will effect upward movement of the pinion shaft, this action being effected without affecting the position ofthe rackbars. When the parts have been raised high enough to withdraw the nut from engagement with the pins 3 of the body portion, a proper turning movement is applied to the wheel orcap and all of the parts mentioned as affected by the lifting action, are likewise turned, and the pinion shaft obviously imparts endwise movement to the rack bars so as to effect expansion of the grinding diameter of the device or contraction thereof, as the case may be. The operation mentioned is for the purpose of quickly expanding the device until the grinding elements are arrestedby contacting vwith the wall of a cylinder in the application ofthe device for operation on the cylinder.

Assuming that the device in its contracted form has been placed within a cylinder preliminarily to the grinding thereof, and the parts have been:manipulated as explained to expand the device, the operator next pushes'the .cap and the affected parts downward until certain of the holes of the nut 12 are engaged with the pins 3 of the body portion. To apply further pressure or adjustment of the grinding elements on the cylinder, the operator canthen impart a slight clockwise turning movement to the cap or wheel, the nut at this time being incapable of rotation by reason of its interlocked relation with Fitting over and upon the,

the pins of the body portion. This turning movement of the wheel or cap, because the wheel or cap is bearing downwardly against the dome, effects rotation but not endwise movement of thebolt. The latter therefore, turning in the threaded bore 17, effects endwise 'movement of the pinion shaft, and the engagement of the coarse threads of the latter with the threaded bore of the nut, effects turning movement of said pinion shaft, and said shaft in turning imparts outward thrust on the rack bars and hence of the grinding elements on the wall of the cylinder. To retract the grinding elements, the cap is turned counter-clockwise about a quarter turn, as that is sufficient to withdraw the grinding elements enough to permit withdrawal from the cylinder.

When the parts have been adjusted to grinding relation within a cylinder as explained, the body portion 1 is rotated by any suitable means, and ascustomary with devices of this character, the device as a whole is also reciprocated so that it shall cover in its operation, the entire length of the cylinder.

In theconstruction shown, a shaft 26 driven a forked end Z'L Which straddles the wheel and nut 12 and is pivoted at diametrically opposite points as at 28 to a ring 29 surrounding the upper end of the body portion, and at right angles to the pivotal points 28, the ring is equipped with pivot bolts 30 which extend into the body portion, the arrangement being such that the ring and shaft have a universal joint connection with the body portion so that whether the shaft 26 stands in axial alinement or not with the body portion, the latter can be properly operated to effect the grinding operation.

After the grinding operation is completed the device, can be withdrawn from the cylinder and the grinding elements can be replaced. by finer ones to give a smoother finish, and finally polishing elements may be substituted if desired, for the purpose of giving a perfectly clean and smooth finish to the interior of the cylinder. In this connection it is desired to call attention to the fact that toavoidthe necessity of exercising particularcare in raising the nut from engage ment with the, pins of the body portion, the lower endiof, the pinion shaft is provided with a pair of circular grooves 31 and 32' spaced apart a somewhat greater distance than the length of .mentary..groove 33 containing .a spring ring 34 which. normally also. engages thefgroove 31,01 the pinion shaft. When the latter is raised with the cap and nut, the spring ring is forced to expand until wholly within groove "33', and as the lower groove 32 of thepinion shaft comes within the plane. of the spring 34, thelattersnaps into the,groove"32, without totally withdrawing from groove'33, and thus offers a yielding resistance to accidental withdrawal of the pinion shaft wholly from the body portion, as might occur if the raising action was too vigorous and careless. It is obvious of course that'a pull can be applied which will permit the pinion shaft to be wholly withdrawn from the body portion, as the-spring ring 34 will. thenxof course expand completely out of groove 32 in the same manner as described with reference'to groove 31.

From the above description it will be apparent that I have produced a cylinder grinding device possessing the features of advantage set forth as desirable in the statement of the objects of the invention, and while I have illustrated and described a desirable embodiment, it is to be understood that various changes of detail construction may be resorted to within the principle of construction and mode of operation involved, and" hence within the spirit and scope of the appended claims.

I claim:

1. A device of the characterdescribed com- I prising a body portion having an axialbore and two sets of cross passages disposed atdifferent' angles across the body portion, and communicating with the said bore, rack bars extending through said cross passages, abrasive elements paralleling and at opposite sides of the body portion, a nut interlocked with the pins, a pinion.

shaft journaled in the body portion and provided with a threaded portion engaging the bore of the nut, and connections for transmitting power from the shaft when turned, to effect inward or outward adjustment of the grinding elements relative to the body portion.

3. The combination of a rotatable body portion, apinion shaft disposed axially therein, rack bars extending crosswise of the body portion and engaging the pinion shaft, work-engaging devices carried by the rack bars, and means-to simultane ously effect longitudinal and turning movement of the pinion shaft to adjust the work-engaging devices outwardly or inwardly relative to the body portion.

4. The combination of a body portion, workengaging elements carried by and at opposite sides of and parallel with the body'portion, a shaft journaled in the body portion and'adapted to be turned for adjustment of the work-engaging elements, and provided with a threaded bore, a

nut detachably interlocked with the'body por' tion and threaded on saidshaft, a thrust plate rigid with the. nut, aica'p resting on the said plate,

and a bolt rigidly depending from the cap through the thrust plate and engaging the threaded bore of the shaft, and provided with a collar bearing against the underside of the thrust plate.

5. The combination of a-body portion, workengaging elements carried by and at opposite sides of and parallel with the body portion, a shaft journaled in the body portion and adapted to be turned for adjustment of the work-engaging elements, and provided with a threaded bore,

a nut detachably interlocked with the body portion and threaded on said shaft, athrust plate rigid with the nut, a cap resting on the said plate,

a bolt rigidly depending from the cap through the thrust plate and engaging the threaded bore of the shaft, and provided with a collar bearing against the underside of the thrust plate, and a spring washer interposed between and engaged by the cap and the nut.

6. In a device of the character described, a re.- tatable body portion having a longitudinal bore and cross passages intersecting the bore, workengaging elements, rack-bars rigid with said elements and engaging the respective cross passages of the body portion, a toothed shaft in the said bore and engaging the rack-bars, a part above the upper end of and interlocked with the body portion, a cap above said part, means whereby rotation of the cap shall effect endwise movement of the shaft and means whereby the part tationof the shaft during the endwise movement thereof.

7. In -a device of the character described, a rotatable body portion having a longitudinal bore and a top pin paralleling'the bore, a part upon and a connectionbetween the cap and the shaft adapted, when the cap is moved upward from the body portion; to effect like movement of the shaft and cause the latter to withdraw the said part from engagement with said pin.

8. In a rotary grinding a polishing tool, a shaft of gear form in cross-sectionfrom one end to an intermediate point in its length, and of spiral grooved form in cross-section from the other end to an intermediate point in its length, and provided, also with a threaded bore at the spirally grooved end.

EUGENE F. COOK.

interlocked with the body portion shall effect rothe body portion and provided with a hole nor- 7 mally engaging the pin, a shaft in the bore having a threaded engagement with said part, a cap, 

